Digitally controlled convergence system

Abstract

A multi-channel, multiple deflection waveform generator for a convergence control system and the like comprises an analog circuit source for a plurality of basic waveforms and a basic waveform processor for each of a plurality of channels. Each of the channel processors may comprise a plurality of circuits for modifying the basic waveforms, a circuit for combining any combination of modified waveforms to form a specifically configured composite waveform and a remotely controllable shift register for independently setting each of the plurality of modifying circuits from a central control, for example, by means of an existing serial bus. Each of the modifying circuits may comprise a first part for altering the scale of one of the basic waveforms and a second part for altering the gain of the same one of the basic waveforms. Each of the remotely controlled shift registers has a setting for selecting any one of a plurality of predetermined operating conditions for one of the first and second parts of the modifying circuit. In one embodiment, the operating condition for the other one of the first and second modifying parts may be preselected and fixed. In another embodiment, another shift register may store a second setting for selecting any one of a second plurality of predetermined operating conditions for the other of the first and second parts of the modifying circuit. Each channel processor may be remotely controlled to generate a specifically configured composite waveform, for example, for driving a different one of a plurality of deflection coils in the convergence yokes of a projection television. The invention may also be embodied as a custom analog waveform generating module adapted to operate within the digital control architecture of a host apparatus, such as a television, video recorder or the like.

What is claimed is: 
     
       1. A multiple deflection waveform generator, comprising: an analog source for generating a plurality of basic waveforms having different waveshapes;   a plurality of signal processors coupled to the analog circuit source and each comprising: a plurality of means for modifying different ones of the basic waveforms by factors of scale and gain to produce modified waveforms, each modified waveform having substantially the same waveshape as when generated by the analog source but a different amplitude, at least one of the scale and gain factors being modified according to one of a plurality of predetermined operations;   means responsive to digital control signals for setting each of the modifying means to select one of the predetermined operating conditions; and,   means for combining different ones of the modified waveforms to develop a specifically configured composite deflection waveform; and,     means, for generating the digital control signals for operating the modifying means.   
     
     
       2. The multiple deflection waveform generator of claim 1, wherein the means for generating the digital control signals comprises: means for storing the digital control signals;   means for loading the digital control signals into the storing means; and,   means for transmitting the digital control signals to the modifying means.   
     
     
       3. The multiple deflection waveform generator of claim 1, wherein each of the processes comprises: a modifying circuit for each basic waveform necessary for developing the composite waveform of that processor;   a digital register coupled to each of the modifying circuits for storing the setting; and,   an analog summing circuit coupled to all of the modifying circuits.   
     
     
       4. The multiple deflection waveform generator of claim 2, wherein each of the processors comprises: a modifying circuit for each basic waveform necessary for developing the composite waveform of that processor;   a digital register coupled to each of the modifying circuit for storing the setting; and,   an analog summing circuit coupled to all of the modifying circuits.   
     
     
       5. The multiple deflection waveform generator of claim 2, wherein the storing means comprises a nonvolatile memory. 
     
     
       6. The multiple deflection waveform generator of claim 1, wherein the means for setting the modifying means comprises a nonvolatile memory. 
     
     
       7. The waveform generator of claim 1, wherein each of the processors comprises: sets of first and second modifying circuits for respectively altering the scale and gain of one of the basic waveforms; and,   a shift register for each set for selecting one of the predetermined operating conditions for one of the first and second modifying circuits responsive to the digital control signals.   
     
     
       8. The waveform generator of claim 7, wherein an operating condition for the other one of the first and second modifying circuits is preselected and fixed. 
     
     
       9. The waveform generator of claim 7, further comprising another shift register for each set for selecting one of the predetermined operating conditions for the other of the first and second modifying circuits. 
     
     
       10. A digitally controlled convergence system, comprising: an analog source for generating a plurality of basic deflection waveforms having different waveshapes;   a plurality of signal processors coupled to the analog circuit source and each comprising: means for modifying selected ones of the basic deflection waveforms by factors of scale and gain to produce modified waveforms, each modified waveform having substantially the same waveshape as when generated by the analog source but a different amplitude, at least one of the scale and gain factors being modified according to one of a plurality of predetermined operations;   means responsive to digital control signals for setting each of the modifying means to select one of the predetermined operating conditions; and,   means for combining different ones of the selected modified waveforms to develop a specifically configured composite deflection waveform for driving a deflection coil in a convergence yoke; and,   means for generating the digital control signals for remotely operating the modifying means.     
     
     
       11. The convergence control system of claim 10, wherein each of the processors further comprises: a modifying circuit for each of the selected basic waveforms;   a digital register coupled to each of the modifying circuits for storing the setting; and,   an analog summing circuit coupled to all of the modifying circuits.   
     
     
       12. The convergence control system of claim 10, wherein each of the processors comprises: sets of scale and gain modifying circuits for respectively altering the scale and gain of one of the basic waveforms; and,   a shift register for each set for selecting one of the predetermined operating conditions for one of the scale and gain modifying circuits.   
     
     
       13. The convergence control system of claim 12, wherein an operating condition for the other one of the scale and gain modifying circuits is preselected and fixed. 
     
     
       14. The convergence control system of claim 12, further comprising another register for each set for selecting one of the predetermined operating conditions for the other of the scale and gain modifying circuits. 
     
     
       15. The convergence control system of claim 12, wherein each of the scale modifying circuits comprises a resistive dividing network. 
     
     
       16. The convergence control system of claim 12, wherein each of the gain modifying circuits comprises an R-2R network with a plurality of switch means. 
     
     
       17. An analog waveform generating module, adapted to operate within televisions, video recorders and the like having a digital control architecture, comprising: an analog circuit source for generating a plurality of basic waveforms having different waveshapes;   respective pluralities of first and second means for modifying different ones of the basic waveforms to produce modified waveforms, each modified waveform having substantially the same waveshape as when generated by the analog source but a different amplitude;   one of the respective pluralities of first and second modifying means being responsive to digital control signals for respectively modifying the amplitudes of the basic waveforms by one of scale and gain factors, according to one of a plurality of predetermined operations and the other of the respective pluralities of first and second modifying means further modifying the amplitudes of the basic waveforms by the other one of the scale and gain factors;   means for storing a digital setting for controlling each of the plurality of first modifying means;   an analog circuit for combining the scale and gain modified waveforms to form a specifically configured composite waveform; and,   a digital processor for loading the digital settings into the storing means in accordance with information provided by the digital control architecture.   
     
     
       18. The analog waveform generating module of claim 17, wherein the digital processor comprises: a decoder for changing a serial data stream received from the digital control architecture into a parallel data format; and,   a parallel data bus connecting the decoder with each of the storing means.   
     
     
       19. The analog waveform generating module of claim 17, wherein each of the plurality of first modifying means comprises a scale modifying circuit for altering the scale of one of the basic waveforms and each of the plurality of second modifying means comprises a scale modifying circuit for altering the scale of the same one of the basic waveforms. 
     
     
       20. The analog waveform generating module of claim 19, wherein the scale modifying circuits comprise resistive dividing networks; and, the gain modifying circuits comprise R-2R networks, each with a plurality of switch means. 
     
     
       21. The analog waveform generating module of claim 17, wherein an operating condition for each of the second modifying means is preselected and fixed. 
     
     
       22. The analog waveform generating module of claim 17, comprising a plurality of analog summing circuits for generating a plurality of specifically configured composite waveforms. 
     
     
       23. A composite waveform generator, comprising: an analog source for generating at least two basic waveforms having different waveshapes;   means associated with each of the least two basic waveforms for modifying the associated basic waveform by factors of scale and gain to produce a modified waveform having substantially the same waveshape as when generated by the analog source but a different amplitude;   a digital shift register for setting each of the scale and gain factors according to one of a plurality of predetermined operating conditions; and,   means for combining the modified waveforms to develop a specifically configured composite deflection waveform.   
     
     
       24. The composite waveform generator of claim 23 comprising: a scale modifying circuit for altering the scale of each of the basic waveforms;   a gain modifying circuit for altering the gain of the same one of the basic waveforms; and,   an analog summing circuit coupled to all of the gain modifying circuits.   
     
     
       25. The composite waveform generator of claim 24, wherein: the scale modifying circuits comprise resistive dividing networks;   the gain modifying circuits comprise R-2R networks, each with a plurality of switch means coupled to the shift register; and,   the analog summing circuit comprises an operational amplifier.